Process of coating with preservative compositions



mantras S??? Patented May 7, 1946 Vaclav Edwin a. Littman.

m. No Drawing. Application December 28, 19.40;

h 7 Serial No. 372,178 i u r C t This invention relates to the coatingof cellulosic materials with fusible saltsoi' organic acids and itrelates particularly to mildew-proofing or rot-proofing of fabrics orother textile and paper products. j

The use of coating agents on cellulosic materials such as fabrics, paperand rope is well known. Such coatings have generally been applied-toarticles without regard to rot-proofing characteristics againstmicro-organisms such as iungiior marine algae. Where beenapplied from avolatile solvent; has .been experienced in securing even depositionamount greatly in excess of the threshold-quad tity required to poisonthe attacking micror.ithe:fm ds;i s=fi edgi i i invention; it has beenfoundthatimproyedprof of cellulose: materialagainst? micro-1 obtained;"w u its.

'fm'ther'fq that? bathe t i dic-Le ann tion; I the; p l'lysical{properties 'of {the article such as rope}- cord, duck, -f;etc.', remainlargely unchanged. Added stiffness,- s'li p l ess, etcqareeither absentor reduced to aminirmim when the articles are treated according tothemethods described. V '1' The fusible metallic salts of organic acidsthat are used in the practice of thisinvention are those which are "liqi al' fi out'lmflc. solid or very viscous-at ordinary temperatures andwhich do not flow appreciably at.about""jC.- While saltsfallingwithinthefusible range of about 0-150 C. maybe used; thosefusingbetween about C. and 125 C. are preferred. Salts which may be used inthe practice of this invention are cc per naphthe nate, oleate,resinate, etc. Zinc naphthenates, resinates and oleates are .almsed.Uranium, thorium, cerium and nickel salts of these organic acids maylikewise be used. Mixtures of these various salts that fuse in the aboverange may likewise be used.

The fusible metallic salts of the organic acids are generally dissolvedin volatile solvents such as low boiling naphthas that are used in thepaint or dry cleaning business, for example, Varsol and V. M. P.naphthas which have narrow boilin ranges between 150 C. and 325 C. Othervolatile solvents such as ketones, esters and alcohols or mixtures ofthese various volatile solvents may be used. By a volatile solvent ismeant those that rot-proofing coatings have nd covering of the cellulosefibres without using an excessive amount of protective matcrial; fan' 1some PROCESS OF COATING WITH PRES ERVATIVE COMPOSITIONS Westfield, andJohn B. M. j Klotz, Montclair N. J., assignors to Stanco,

I modify the physical characteristics of the treated eliminated.

to heat "sufllcient'to'cause the; depositeds lt id ll qnfia lz'.zexcessive-uuantities'ofpreservativm It'has c H and penetrate intotheinter-fibre W first applied tothe fabric and dried uneven distributionof LI 1...! Lu -vwill evaporate at" atmospheric temperatures withoutleaving any appreciable residue. If desired, dryingoils such asChina-wood oil, linseed oil, etc may likewise be incorporated in thesolvents.

The fusiblesalts of the above organic acids have, in the past, beendissolved in these various solvents and applied to the surface of thecellulosic material by means of a brush, spray or by dipping. After;air-drying, the treatedarticles were placed into use.- By the abovetreatment.

protective material was obtained because of-yariables mtroduced into thecoating operation.- 'Undesirable stiffness. j hay also :result from. theabove method of application of. fusible f-metailic salts of organicacidg; the present invention, largely these l at f a z'i r a difi fia fic fyiie efii n-r tile at a st ev r e adi h n IWPJ'W flow; 1 whereby Iorganic stifiness 'impartedfto' th or feel, that the fabric had beentreated vithlfusible metallic" saltwof the organic. acidiffflhetemporary stiffness is gone and the coated iabric appears to retain itsoriginal flexibility and ability to be bent or handled without therupture arm of the treatedmaterial orinterference w'ith f-iiturefabrication.....'...-- ..e -LNonmalatile solvents'may ialso beused, forexample, the lighter grades of migeral white oil, l cordage oils whichmay or may ndt'b'e partly g emulsified, fuel oil, etc. Thesenon-volatile solvents are generally used when it is desirable to preparea cellulosic material whose fibers are being lubricated or where it isnecessary to waterproof the material. This treated fabric likewise, whenfirst treated appears to be stiffened to a certain extent but thistiffness is readily overcome upon heating the fabric and the original'T-wf' lvarious types. .otnaphthenate emulsions may, J b a i dto ri -J bai na r range is between 40 and 125 C. though tempera tures outside thisrange may be used under certain operating conditions. The method ofapplying heat to the fabric containing the fusible salt is per serelatively unimportant. In prac- 5 tice, heating is accomplished bymeans or a heated drying or squeeze roll or in a drying tunnel orsimilar device using circulating heated air or other gas.

pper base: Grams Copper naphthenate 200 Paraflin 200 Aluminumnaphthenate 50 The bases are prepared by melting together the productsshown. Temperatures as high as 700 F. may be used.

Zine emulsion The quantity or coating composition generally J To 300 g.boiling water add 9 g. stearic acid and applied may be greatly varied,that is, where it i necessary only to maintain material'strength-Q andnot waterproof it to a great extent, small quantities may be used and alight coatingmay be applied but on the other hand, where the ma terial iused to coat cable, rope or cord and a definite lubricating andwaterprooflng reftect is desired, enough of the material is added tocoat I it to a substantial degree. Therefore the propor- H tions on apercentage basis may be fromabout 2 to 15%, based upon the cellulosicmaterial. Y

It is not necessary to use a solvent as themhicle for the fusiblemetallic salts of organic acids. Most fabrics are finished by a wetprocess. and drying is the final operation. The use or solvent solutionsof preservatives introduces -one or -two additional operations therebyraising. the cost of A the treatment as well ascreating a firehaz'ard'.It is a general practice .to' apply preservatives from the size bathwhicli'process adds no appre- 3o ciable cost, but that for matei'ial s,to the: on I tion.

thenate femulsionlslprepaied .,..;fr0m, 'i'zinc; naph- 5 yit' isnecessai-ribn rt ta thsj m s a or'e'ii abbl a i ff gm i i fhqiibe apfpliedeither 'hot jorfjcoldg'thoughjtemperatures .be tweenab0utffZ125200fiE seem to produce the .resultsil'f Emulsions or theabove type are for the application or preservative materialjonlyij I 11-1 Where it is desiredto increase water repellency 5o flw'ell asresistance; to" rotting, naphtlienate emulsions containing wax for asimilar fmate'rial Two mulsionsfor the "and dried at an elevatedtemperature.

3.5 g. triethanol amine and stir to a smooth soap. To this solution add88 g. zinc base heated to 200 F. and previously mixed with 10 g. of anoil soluble :sulphonate known as 302-8 (Stance product) and stir veryrapidly for 5 minutes and occasionally until cool.'-'- Copper emulsionemulsion is'prepared as above except that 20"g.'of 302-S is required.

, These emulsions may be applied full strength or diluted with hot wateras desired.

After passing through the squeeze rolls, the fabric is passed through adilute acid bath such as 5% acetic acid, again queezed through rollsWhen used. full strength, the zinc naphthenate emulsion leads to thedeposition of 18-19% material on No. 6 duckwhereas if diluted with anequal weight of water a -10% depositis obtained. v For use as waterrepellents only emulsions con- -g taining paraffin or wax and aluminumor ceri naphthenates may be prepared. The function or the last twomaterials is to decrease the tempera- I ture efiectonjparaflin orsimi1ar waxes; and'fre V ,Lduce-thefsweating at elevated temperaturesand T embrittl'ement at low temperatures.) I 1; Processor 'coaacellulosicfibrous'ma rial without substantially changing the originalphysical properties'or flexibility and abiiityto be r bent withoutrupturing the materials which com; I

p' sf preparing an iemulsion or 1.copp r; -uapn;

'te; aluminafflnaphthenatelfparaiiin water and an emulsifier;impregnating a.. cellulosic n;

,?I'b 6-' s m t a ubmitting the cellulosic fibrous materiahtopressuretoexpel the majonportion oi the water 1 and subjectingto a temperaturesufliciently high to cause the whole" fusible a'net'allic salt of theorganic acid to fuse and penetrate intotheinterfibrespaces. i-

j 2. Processor coating a cellulosic .fibrousmatee f rial according toclaim '1 in-which the emulsion

